Hospitalization is one of the most common precipitants of disability, and skilled nursing facilities (SNFs) are ncreasingly the site where the most vulnerable older adults receive the post-acute medical and rehabilitative care crucial for their functional recovery. Changes in the health care system have led to patients' being discharged from the hospital quicker and sicker, but the structure of SNF-based post-acute care (PAC) has not kept up with their increasing medical illness. Failure to regain pre-hospitalization function during this critical juncture results in morbidity, institutionalization, and even death, yet there is little evidence to guide SNF-based PAC. Clinical observations suggest that medical instability, delirium, and depressive symptoms are common but often unrecognized among PAC patients, interfere with rehabilitation and functional recovery, and are modifiable. Delirium and depression have well developed assessment tools, while medical instability can be identified with simple markers such as vital signs and symptoms at rest and with exercise. The overall goal of the proposed research is to improve the management of medically ill patients in PAC and ultimately to improve functional recovery. The specific aims are 1) to identify SNF-based PAC patients with substantial yet modifiable risk of poor functional recovery using data from the Medicare Current Beneficiary Survey, 2) to follow a prospective cohort of 180 new admissions to SNF-based PAC to determine the effect of medical instability, delirium, and depressive symptoms on function after one week and at SNF discharge, and 3) to pilot test an intervention to screen for these three factors on admission to SNF-based PAC. The proposed career development and research plans will build upon analytic and methodologic skills gained through my doctoral training in Investigative Medicine. I wish to add competencies in 1) analysis of administrative data; 2) primary research design and implementation, and 3) intervention development for the SNF setting. Upon completion of the proposed work, I will have built a strong evidence base for and gained extensive experience with the PAC population and the SNF setting. I will then be prepared to design, secure funding for, and implement a full-scale clinical trial of a refined intervention to address medical instability, delirium, and depressive symptoms, and ultimately to improve functional recovery in SNF-based PAC. Public health relevance: Failure to recover from functional decline after hospitalization can be catastrophic for older adults and costly to the health care system. If older adults admitted to nursing homes for additional post-acute care are still medically unstable, confused, and depressed from their acute illness, they may have trouble participating in rehabilitation and regaining their previous function. This research will determine the effect of these factors on functional recovery among older adults in nursing homes for rehabilitation and develop a method for identifying these problems when patients are admitted to the nursing home.